Which wheels size for best autocross/ track/ street performance?

When I bought my RSX Type S it already had 17 inch rims on it. Now that I am overhauling a lot of things on the car I am wanting to address the wheel/tire issue. I know 17inch rims "look better" I guess but im not interested in looks as much as I am performance i.e. contact patch, sidewall flex, unsprung weight. Should I stick with 17inch rims that are more expensive to find tires for? Or should I go back to 16inchrims which they come with from the factory anyway? Im interested in 16s because I could cut cost and weight! btw fyi the Japanese version of my car is equipped with 17inch rims...

Autocross, track, and street performance comprise of different parameters. For autocross and street driving, you won't be able to feel or measure an increase in performance from lightweight wheels, because companies and magazines have tested it several times. 16s are probably the way to go because you will end up buying performance tires a little more often than street tires depending on how much you track your car. Performance tires should still last quite a while for mostly autocross.

I run 16's on my e30,tire selection sucks....the end.

17's have a much better tire selection than 16's. I ran 225/45-17's on my RSX for autocross in Street Touring. Probably could have run wider rubber, but the car was fun and locally competitive as it was.

Yeah, research the tire size you want first, then buy wheels to fit.

ok so ill just stick with 17s that's sounds like the consensus

Tire choices dictates wheel size to me. 16" is no man's land. Too big for a Miata, too small for anything else. If nobody wants a tire size, they pretty much don't make it.

Smallest wheel that will clear your brakes with decent tire selection is the answer to the question I think you should be asking. Wider is not necessarily better on tires. For example, on a 15x6 wheel, many prefer and are faster with a 195 over a 205, wider not better, shocking right!

If the tire is stretched a bit, it will tend to deform a little less when you turn.

Wider wheels is pretty much always better

Mr_Clutch42 wrote: Autocross, track, and street performance comprise of different parameters. For autocross and street driving, you won't be able to feel or measure an increase in performance from lightweight wheels, because companies and magazines have tested it several times. 16s are probably the way to go because you will end up buying performance tires a little more often than street tires depending on how much you track your car. Performance tires should still last quite a while for mostly autocross.

only problem with 16's is the lack of tire availability … 15's and 17's seem to have more choices … plenty of 16's out there, just not as big a choice as the others

Pick tire size first.

225/45/17s minimum. An RSX with driver is a tank at around 3,000 lbs., 1,800 of it on the front wheels with McPhersons. 9 1/2" to 10" tread (up front) is even better.

Do you care what autocross class you end up in? Because that's step one, if you do. If not, figure out what tire size most people are using for your chassis, and start there. Its probably a 17.

In reply to wbjones: It depends on what you're going to use them for. On my E36 all the top Extreme Summer tires come in my size in 16" for autocross and track days. For daily driving with the other category summer tires, I'm still ok. I guess it depends on the specific size. I just checked Tire Rack, and wow! 17" tires have a HUGE selection.

that was my point … 17 is the new 15 … it's good that you've got choices in 16 …

You have a point. In a couple of years, a couple of the Extreme performance summer tires won't be sold in 16" sizes at all.

Ok so ill stick with my 17s...and wrap them in 225/45/17s....unless a wideir tire is better....any recommendations for widening the track up front? Wont be for a while obviously but i see people with rsx running roll center adjusters and liking them

Wider is almost always better in autocross, if you have the wheels to support it.

As Swank said, if you have the wheel width to support the tread width. 7" wheels aren't perfect for 225s but they'll do ok. I used 16x6.5 wheels on 8.5" tread starting out and they were fine. Not as good as 8.5" wheels, though, as you get more sidewall flex.

Rcas aren't really needed for the RSX until you have a drop lower than 3/4" at least. That doesn't take into consideration balancing front to back, but there is something presently being developed on that for the rear and should be announced soon. I'll be getting this product to test hopefully this spring along with some other goodies.

Widening the front track is a big help for the RSX but that's probably not something to think about yet. Type R lcas (without using R hubs or the correct R wheel spacing), increased offset wheels, wheel spacers, and camber will increase your track. Stock track is about 58" and you can go to a bit over 62" before the change in geometry offsets the benefits of a wider track. My Ep is also wider in the rear but not as much as the front. About 61.5".

Some of these mods will take you into faster classes but I don't follow any of the class rules.

Or you could just say screw it, spend a bunch of money to fit 15s and do this ;

Hasbro wrote: As Swank said, if you have the wheel width to support the tread width. 7" wheels aren't perfect for 225s but they'll do ok. I used 16x6.5 wheels on 8.5" tread starting out and they were fine. Not as good as 8.5" wheels, though, as you get more sidewall flex. Rcas aren't really needed for the RSX until you have a drop lower than 3/4" at least. That doesn't take into consideration balancing front to back, but there is something presently being developed on that for the rear and should be announced soon. I'll be getting this product to test hopefully this spring along with some other goodies. Widening the front track is a big help for the RSX but that's probably not something to think about yet. Type R lcas (without using R hubs or the correct R wheel spacing), increased offset wheels, wheel spacers, and camber will increase your track. Stock track is about 58" and you can go to a bit over 62" before the change in geometry offsets the benefits of a wider track. My Ep is also wider in the rear but not as much as the front. About 61.5". Some of these mods will take you into faster classes but I don't follow any of the class rules. Or you could just say screw it, spend a bunch of money to fit 15s and do this ;

Wait wats that?? Lol a 15 inch rim?

And wats the widest tire i should run on 17x7?

a 225 would be optimal (tread width = rim width… and even the 225 would probably be a smidgen wider than optimal… I run 195's on 7" rims) … but you could probably get away with 235's or even 255's … both will be pinched a bit and not give you their very best … but still should be "ok"

I've done 235 autox rubber on a 7.5" rim and had issues with sidewall flex.....so I wouldn't think they or a 255 would work on a 7" wheel without running all the pressure.

My 235's loved 8" wheels though.

The bigger the wheel, the lower the aspect ratio. Michelin once made a race tire with 19" wheel and something like a 15 or 20 aspect ratio. In theory this improves handling, not so good for the street.

Gotcha...225 it is